561
FNCA52 TJSJ 310804 AAA
FWFSJU
FIRE WEATHER PLANNING FORECAST FOR PUERTO RICO...UPDATED
NATIONAL WEATHER SERVICE SAN JUAN PR
404 AM AST FRI JUL 31 2026
DISCUSSION
MINIMUM RELATIVE HUMIDITY VALUES SHOULD REMAIN NEAR OR ABOVE
CRITICAL THRESHOLDS TODAY. INFLUX OF MOISTURE DURING THE WEEKEND
COULD AID IN IMPROVING OVERALL FIRE WEATHER CONDITIONS. HOWEVER,
CRITICALLY DRY FUELS PERSIST ACROSS SOUTHERN PUERTO RICO AND ST.
CROIX, WITH KEETCH-BYRAM DROUGHT INDEX (KBDI) VALUES REMAINING
WELL ABOVE THE CRITICAL THRESHOLD. EAST TO EAST- SOUTHEAST WINDS
ARE EXPECTED TO REMAIN ABOVE OR NEAR THE CRITICAL LEVELS THROUGH
AT LEAST TODAY, SLIGHTLY WHICH COULD PROMOTE THE RAPID SPREAD OF
ANY FIRE THAT DEVELOPS. RESIDENTS AND VISITORS SHOULD AVOID
OUTDOOR BURNING AND EXERCISE CAUTION WITH ACTIVITIES THAT COULD
GENERATE SPARKS OR OPEN FLAMES, ESPECIALLY ACROSS AREAS WITH
CRITICALLY DRY VEGETATION.
PRZ014-312015-
SOUTHEAST COASTAL PLAINS-
404 AM AST FRI JUL 31 2026
TODAY TONIGHT SAT
CLOUD COVER PCLDY MCLEAR PCLDY
PRECIP TYPE SHOWERS SHOWERS TSTMS
CHANCE PRECIP (%) 20 10 50
TEMP (24H TREND) 91 (-1) 74 (-3) 90
RH % (24H TREND) 52 (-5) 93 (+6) 56
WIND 20FT/EARLY(MPH) E 16 E 14 E 17
WIND 20FT/LATE(MPH) E 19 E 11 E 18
MIXING HGT(FT-AGL/MSL)5810 4750
TRANSPORT WND (MPH) E 20 E 17
VENT RATE (KT-FT) 98770 71250
DISPERSION 5 5
DSI 6 4 6
RH RECOVERY EXCELLENT
REMARKS...NONE.
PRZ015-312015-
SOUTHERN HILLS-
404 AM AST FRI JUL 31 2026
TODAY TONIGHT SAT
CLOUD COVER PCLDY MCLEAR PCLDY
PRECIP TYPE SHOWERS SHOWERS TSTMS
CHANCE PRECIP (%) 40 10 50
TEMP (24H TREND) 88 (+1) 70 (-3) 88
RH % (24H TREND) 58 (-3) 98 (+7) 62
WIND 20FT/EARLY(MPH) E 13 E 12 E 13
WIND 20FT/LATE(MPH) E 14 E 12 SE 13
MIXING HGT(FT-AGL/MSL)6400 5370
TRANSPORT WND (MPH) E 17 E 17
VENT RATE (KT-FT) 96000 80550
DISPERSION 5 5
DSI 6 3 6
RH RECOVERY EXCELLENT
REMARKS...NONE.
PRZ016-312015-
NORTH COASTAL PLAINS-
404 AM AST FRI JUL 31 2026
TODAY TONIGHT SAT
CLOUD COVER PCLDY MCLEAR PCLDY
PRECIP TYPE SHOWERS SHOWERS TSTMS
CHANCE PRECIP (%) 40 10 60
TEMP (24H TREND) 90 (-1) 73 (-4) 90
RH % (24H TREND) 59 (-4) 97 (+5) 60
WIND 20FT/EARLY(MPH) E 17 E 19 E 14
WIND 20FT/LATE(MPH) E 23 E 11 E 21
MIXING HGT(FT-AGL/MSL)5580 5270
TRANSPORT WND (MPH) E 20 E 16
VENT RATE (KT-FT) 94860 73780
DISPERSION 5 5
DSI 6 5 6
RH RECOVERY EXCELLENT
REMARKS...NONE.
PRZ017-312015-
NORTHERN HILLS-
404 AM AST FRI JUL 31 2026
TODAY TONIGHT SAT
CLOUD COVER PCLDY MCLEAR PCLDY
PRECIP TYPE SHOWERS SHOWERS TSTMS
CHANCE PRECIP (%) 50 10 60
TEMP (24H TREND) 89 (-1) 70 (-4) 89
RH % (24H TREND) 63 (+2) 100 (+4) 63
WIND 20FT/EARLY(MPH) E 14 E 17 E 13
WIND 20FT/LATE(MPH) E 20 E 9 E 18
MIXING HGT(FT-AGL/MSL)6890 6330
TRANSPORT WND (MPH) E 16 E 14
VENT RATE (KT-FT) 96460 75960
DISPERSION 5 5
DSI 6 3 6
RH RECOVERY EXCELLENT
REMARKS...NONE.
PRZ018-312015-
WEST COAST-
404 AM AST FRI JUL 31 2026
TODAY TONIGHT SAT
CLOUD COVER PCLDY MCLEAR PCLDY
PRECIP TYPE TSTMS SHOWERS TSTMS
CHANCE PRECIP (%) 60 30 50
TEMP (24H TREND) 93 (0) 73 (-1) 93
RH % (24H TREND) 59 (-2) 98 (+5) 60
WIND 20FT/EARLY(MPH) E 13 E 12 E 13
WIND 20FT/LATE(MPH) E 14 E 10 SE 14
MIXING HGT(FT-AGL/MSL)5300 4400
TRANSPORT WND (MPH) E 9 E 13
VENT RATE (KT-FT) 42400 48400
DISPERSION 5 5
DSI 6 3 6
RH RECOVERY EXCELLENT
REMARKS...NONE.
PRZ019-312015-
EASTERN INTERIOR-
404 AM AST FRI JUL 31 2026
TODAY TONIGHT SAT
CLOUD COVER PCLDY MCLEAR PCLDY
PRECIP TYPE SHOWERS SHOWERS TSTMS
CHANCE PRECIP (%) 60 20 70
TEMP (24H TREND) 89 (0) 71 (-4) 89
RH % (24H TREND) 58 (-4) 100 (+7) 61
WIND 20FT/EARLY(MPH) E 14 E 13 E 14
WIND 20FT/LATE(MPH) E 14 E 13 E 14
MIXING HGT(FT-AGL/MSL)6750 6030
TRANSPORT WND (MPH) E 17 E 16
VENT RATE (KT-FT) 101250 84420
DISPERSION 5 5
DSI 6 4 6
RH RECOVERY EXCELLENT
REMARKS...NONE.
PRZ022-312015-
LUQUILLO MOUNTAIN RANGE-
404 AM AST FRI JUL 31 2026
TODAY TONIGHT SAT
CLOUD COVER PCLDY PCLDY MCLDY
PRECIP TYPE SHOWERS SHOWERS TSTMS
CHANCE PRECIP (%) 50 40 70
TEMP (24H TREND) 85 (+2) 69 (-4) 84
RH % (24H TREND) 65 (-7) 100 (+3) 68
WIND 20FT/EARLY(MPH) E 12 E 10 E 12
WIND 20FT/LATE(MPH) E 12 E 10 SE 12
MIXING HGT(FT-AGL/MSL)4900 3790
TRANSPORT WND (MPH) E 18 E 18
VENT RATE (KT-FT) 78400 60640
DISPERSION 5 5
DSI 6 5 6
RH RECOVERY EXCELLENT
REMARKS...NONE.
PRZ023-312015-
CENTRAL MOUNTAIN RANGE-
404 AM AST FRI JUL 31 2026
TODAY TONIGHT SAT
CLOUD COVER PCLDY MCLEAR PCLDY
PRECIP TYPE TSTMS SHOWERS TSTMS
CHANCE PRECIP (%) 60 10 60
TEMP (24H TREND) 86 (+1) 67 (-4) 86
RH % (24H TREND) 66 (+1) 100 (+4) 68
WIND 20FT/EARLY(MPH) E 10 E 10 E 10
WIND 20FT/LATE(MPH) E 12 E 6 SE 11
MIXING HGT(FT-AGL/MSL)8130 6720
TRANSPORT WND (MPH) E 12 SE 14
VENT RATE (KT-FT) 81300 80640
DISPERSION 5 5
DSI 6 2 6
RH RECOVERY EXCELLENT
REMARKS...NONE.
PRZ024-312015-
CAYEY MOUNTAIN RANGE-
404 AM AST FRI JUL 31 2026
TODAY TONIGHT SAT
CLOUD COVER PCLDY MCLEAR PCLDY
PRECIP TYPE SHOWERS SHOWERS TSTMS
CHANCE PRECIP (%) 40 20 70
TEMP (24H TREND) 85 (+1) 69 (-4) 84
RH % (24H TREND) 65 (-2) 100 (+3) 70
WIND 20FT/EARLY(MPH) E 12 E 10 E 11
WIND 20FT/LATE(MPH) E 12 E 10 E 11
MIXING HGT(FT-AGL/MSL)5720 4720
TRANSPORT WND (MPH) E 20 E 17
VENT RATE (KT-FT) 97240 70800
DISPERSION 5 5
DSI 6 4 6
RH RECOVERY EXCELLENT
REMARKS...NONE.
PRZ025-312015-
VIEQUES-
404 AM AST FRI JUL 31 2026
TODAY TONIGHT SAT
CLOUD COVER PCLDY PCLDY MCLDY
PRECIP TYPE SHOWERS SHOWERS TSTMS
CHANCE PRECIP (%) 40 30 70
TEMP (24H TREND) 90 (0) 77 (-2) 90
RH % (24H TREND) 55 (-5) 86 (+3) 57
WIND 20FT/EARLY(MPH) E 18 E 17 E 17
WIND 20FT/LATE(MPH) E 17 E 17 E 17
MIXING HGT(FT-AGL/MSL)3940 3450
TRANSPORT WND (MPH) E 22 E 21
VENT RATE (KT-FT) 74860 62100
DISPERSION 5 5
DSI 6 6 6
RH RECOVERY EXCELLENT
REMARKS...NONE.
PRZ026-312015-
CULEBRA-
404 AM AST FRI JUL 31 2026
TODAY TONIGHT SAT
CLOUD COVER PCLDY MCLEAR PCLDY
PRECIP TYPE SHOWERS SHOWERS TSTMS
CHANCE PRECIP (%) 30 20 70
TEMP (24H TREND) 91 (+2) 78 (-2) 91
RH % (24H TREND) 57 (-10) 89 (+5) 59
WIND 20FT/EARLY(MPH) E 17 E 17 E 17
WIND 20FT/LATE(MPH) E 17 E 17 SE 17
MIXING HGT(FT-AGL/MSL)3910 3490
TRANSPORT WND (MPH) E 23 E 22
VENT RATE (KT-FT) 78200 66310
DISPERSION 5 5
DSI 6 6 6
RH RECOVERY EXCELLENT
REMARKS...NONE.
PRZ027-312015-
SOUTHWEST COASTAL PLAINS AND MONA ISLAND-
404 AM AST FRI JUL 31 2026
TODAY TONIGHT SAT
CLOUD COVER MCLEAR MCLEAR MCLEAR
PRECIP TYPE SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 30 10 20
TEMP (24H TREND) 93 (+1) 74 (-2) 92
RH % (24H TREND) 53 (-4) 91 (+6) 55
WIND 20FT/EARLY(MPH) E 18 E 17 E 19
WIND 20FT/LATE(MPH) E 20 E 14 SE 21
MIXING HGT(FT-AGL/MSL)5600 4420
TRANSPORT WND (MPH) E 17 E 21
VENT RATE (KT-FT) 84000 79560
DISPERSION 5 5
DSI 6 4 6
RH RECOVERY EXCELLENT
REMARKS...NONE.
VIZ001-312015-
SAINT THOMAS AND SAINT JOHN-
404 AM AST FRI JUL 31 2026
TODAY TONIGHT SAT
CLOUD COVER PCLDY MCLEAR PCLDY
PRECIP TYPE SHOWERS SHOWERS TSTMS
CHANCE PRECIP (%) 30 20 60
TEMP (24H TREND) 89 (+2) 77 (-3) 88
RH % (24H TREND) 59 (-7) 88 (+5) 61
WIND 20FT/EARLY(MPH) E 17 E 17 E 17
WIND 20FT/LATE(MPH) E 16 E 17 E 17
MIXING HGT(FT-AGL/MSL)3640 3390
TRANSPORT WND (MPH) E 23 E 23
VENT RATE (KT-FT) 72800 67800
DISPERSION 5 5
DSI 6 6 6
RH RECOVERY EXCELLENT
REMARKS...NONE.
VIZ002-312015-
ST CROIX-
404 AM AST FRI JUL 31 2026
TODAY TONIGHT SAT
CLOUD COVER PCLDY PCLDY MCLDY
PRECIP TYPE SHOWERS SHOWERS TSTMS
CHANCE PRECIP (%) 40 30 60
TEMP (24H TREND) 90 (+2) 77 (-3) 89
RH % (24H TREND) 60 (-7) 91 (+5) 63
WIND 20FT/EARLY(MPH) E 16 E 16 E 16
WIND 20FT/LATE(MPH) E 16 E 17 E 16
MIXING HGT(FT-AGL/MSL)4890 3600
TRANSPORT WND (MPH) E 23 SE 17
VENT RATE (KT-FT) 97800 54000
DISPERSION 5 5
DSI 6 6 6
RH RECOVERY EXCELLENT
REMARKS...NONE.
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